Venetian blind tilter construction



Feb. 4, 1941. LORENTZEN 2,230,807

VENETIAN BLIND TILTER CONSTRUCTION Original Filed July 15, 1938 INVENTOR#617 f? lO/F/ZfZf/Za BY m M +4 1 ATTORNEY.

Patented Feb. 4,1941

UNITED STATES VENETIAN BLIND TILTER CONSTRUCTION Hans K. Lorentzen,Montclalr, N. 1., assignor to Lorentzen Hardware Mfg. com, New York, N.Y., a corporation of New York Original application July 15, 1938, SerialNo. 219,303. Divided and this application October 19, 1940, Serial No.361.872

5 Claims. (Cl. 156 -1'l) This invention relates to Venetian blindtilting devices, and it is particularly applicable to such devices ofthe worm-and-gear-type. For convenience, these devices are referred tomerely as 5 tilters". The invention was originally presented in mycopending application Ser. No. 219,- 303 filed July 15, 1938, of whichthis is a division.

Among the general objects of the invention are to simplify themanufacture, reduce the proba- 10 bility of manufacturing errors, reducethe cost,

and increase the reliability of Venetian blind tilters.

Another object of the-invention is to provide a Venetian blind tilterconstruction that better 1 lends itself to rapid economical manufactureon.

a quantity production basis.

Further objects of the invention are to reduce the number of parts andreduce the number of manufacturing operations for Venetian blindtilters.

Variouspther objects will be apparent from the accompanying disclosure.

Fig. 1 of the drawing is a front elevation of a tilter involving thepresent invention, a section of the, pulley being cut away.

Fig. 2 is a side elevation partially in section, showing the tilter ofFig. 1 when viewed from the ,direction of the arrow 2.

a Fig. 3 is an isometric view of a bracket stamping incorporated in thetilter.

Fig. 4 is .an exploded view showing in unassembled relation certainparts of the tilter.

Fig. 5 is a plan view, partially in section, show ing a shaft and pulleyassembly incorporated in the tilter.

Fig. 6 is a perspective view of an oscillatory cord or chain guideincorporated in the tilter.

Fig. 7 is an elevatloriof a pivot stud by which the gear is mounted."

Fig. 8 is a detail section taken on line 88 of Fig. 5.

As shown more particularly in Figs. 1 and 2, the tilter comprises asupporting bracket designatedas a wholeby ill, a worm II, a shaft l2rotatably mounted on the bracket, and a gear l3 pivotally attached tothe bracket and meshingwith the worm. On the forward end of the shaft l2there is a pulley I4 adapted to be driven, for an example, by a cord Ito rotate the worm II in either direction and thereby. oscillate gearl3. Gear 13 is formed on one leg of a U- shaped rocking member l6; andthe other leg Il is slotted at II to detachably receive a tilt barconnecting 55 member (not shown) as is well understood in the art.Pivoted between the pulley l4 and the bracket l0 there is an oscillatorycord guide, designated as a whole by l3.

The supporting bracket I0 is unitary sheetmetal stamping having thevarious parts shown in Fig. 3. This stamping has a horizontal le 20 thatis adapted to be screwed to the head bar or other supporting structurefrom which the Venetian blind is suspended. It also has a vertical leg2| on which the actuating elements of the tilter are mounted. Formedbetween legs and 2| is an impressed rib 22 which strengthens thebracket. Approximately centrally of the vertical leg 2! there is formeda rectangular opening 23 r having its upper edge recessed at 24. Onoppo-' site sides of the opening 23 the metal of the bracket is cut, andpressed into arcuate straps which form journals for the worm shaft l2.One journal is formed by arcuate straps 25 and 26 which are so pressedas to face in opposite directions, and which are separated axially ofthe journal by a space 21 formed by cutting out the metal of thebracket. Similarly on the other side of the opening 23 another journalis formed by arcuate straps 28 and 29 which are pressed out 5 in opposedrelation and are separated axially of the journal by space 30. Thevertical dimension of cut-outs 21 and 30 is greater than the diameter ofshaft l2, to permit the arcuate straps to be so shaped as to'provide theJournals with radial clearance. The purpose of this clearance will bedisclosed later on. Near its bottom the vertical leg 2i of the bracketis'provided with a hole iii to receive the pivot stud of the gear l3. Onthe forward edge of the vertical leg there is a I hook 32 to plvotallysupport the oscillatory cord or chain guide l9.

The shaft I2 is initially formed with a round head 33 adjacent which isa square shank portion 34 (Fig. 5). The pulley I4 is composed of twomore or less conically shaped sheet-metal stampings 35, 35. Thesestampings have radial ribs 36 (eight shown in each stamping) which actto grip the cord l5 and prevent it from slipping on the pulley to anygreat extent. Each of the pulley stampings 35, 35 is provided with acentrally positioned square hole corresponding to the square shank 34 ofthe shaft. The stampings 35, 35 may be identical; and the diagonal ofthe 0 square hole in the stamping is preferably on a diameter which islocated one-quarter of the distance between adjacent radial ribs. Withsuch coordination of the square hole with the ribs, as-- sembly of thetwo stampings to form 'a pulley will bring the ribs 36. on one stampingin staggered relation with the ribs 33 on the other stamping,

as'shown (for example) in Fig. 4. Ribs in staggered relation grip thepulley cord more effective- I 1y than do ribs in aligned relation. Afterthe two pulley stampings have been as- 'sembled onto the square shankportion-of the shaft l2, the axially projecting metal of the shank isswaged by a cylindrical tool, thus displacingthe metal from annularspace 40 and forming an integral collar 4011. This collar tightly bindsthe pulley stampings 35, 35 together and permanently 'afiixes the pulleyM to the shaft l2.

first assembled to the condition of Fig. 5 and then plated, the platingsolution cannot be cleaned out of the crevices and it remains and causescorrosion. This difliculty is eliminated by plating the pulley discs 35,35 and the shaft [2 (or the head 33 thereof) before assembly. Assemblydoes not necessitate replating as the swaging at 40 is hidden behind thepulley I4 where it is not exposed to view. Further advantage arises outof the fact that the manufacturer must supply tilters with diiferenttypes of pulleys, e. g. for operation with cords and for operation withbead chains. Finished pulley parts of the different .types can bestocked, and then assembled with shafts as customers orders require.

Near its center the shaft I2 is swaged to form oppositely projectingfins 42, 42. As shown in Fig. 4, these fins are wedge-shaped in theirplaneaxially of the shaft; and as shown in Fig. 8, they are alsowedge-shaped in a cross-axial plane. On either side of the fins 42, 42there are zones 42a, 42a which are depressed below the contour of theshaft. The purpose of these fins will be pointed out a little later.

The cord guide I!) has a disc portion 43 apertured at 48 and havingatits top an instruck zone 44 perforated at 45. At the bottom, the guideis formed into a throat 46 through which the ends of the cord or chainpass; and from the throat 46 guide wings 41, 41 project upwardly toextend part way around the circumference of the pulley I4.

In assembly, the cord guide I9 is applied to the hook 32, as indicatedin Fig. 4, the hole 45 being placed on the hook and the cord guide beingswung downwardly so that the aperture 48 is aligtned with the journalsin the bracket stamping. The worm ll, preferably a machined brass worm,is positioned in opening 23; and the free end of shaft I2 is thentelescoped through aperture 48 of the cord guide, through the journalformed by straps 28 and 29, through the worm I l and into the journalformed by straps 25 and 26.

This movement is effected with fins 42', 42 positioned in a verticalplane so that they may pass through the journal clearances. When thefins 42, 42 reach the worm II, the pulley and shaft assembly areforcibly telescoped into the worm, so that the fins are forced intodriving and holding engagement with the worm. Thus, mere assembly of theshaft-pulley unit with the bracket and worm, aflixes the worm to theshaft and prevents accidental withdrawal of the shaft. As fins 42, 42enter the worm they displace metal from the worm; and the shaftdepressions 42a, 42a provide space to accommodate this displaced metal.Thus, the assembly operation 'does not result in the formation of burrsat the end of which has a reduced extension-52 that passes through thehole 3i in the bracket and is riveted thereto.

It will be noted that the tilter disclosed provides a simpleconstruction, that the parts are relatively few, and that the assemblyis simple and well adapted for quantity production.

In compliance with the patent statutes, I have disclosed the best formsin which I have contemplated applying my invention, but it will beunderstood that the disclosure is illustrative of the invention and doesnot limit the scope of the same.

.What I claim is:

1.-In a Venetian blind tilter of the type in which a worm-and-gear areassembled with a supporting structure, the worm being on a shaft havingan end which projects forwardly from the supporting structure, and saidforwardly projecting end of the shaft being provided with an operatingpulley; the improvement which comprises: the shaft having a preformedhead on its forwardly projecting end, the pulley being located behindsaid preformed head, and the shaft being swaged behind said pulleywhereby the pulley conceals the swaging when the tilter'is in use, theswaging acting to claintp, the pulley against said preformed head.

2. In a Venetian blind tilter of the type in which a worm-and-gear areassembled with a supporting structure, the worm being on a shaft havingan end which projects forwardly from the supporting structure, and saidforwardly projecting end of the shaft being provided with an operatingpulley; the improvement which comprises: the shaft having a preformedhead 'on its forwardly projecting end and a non-circular shank behindand adjacent to said'head, the shank being enlarged with respect to thesiZe of the shaft, the pulley being located on said shank in drivingrelation thereto, and the shank being swaged behind said pulley wherebythe pulley conceals the swaging when the tilter is in use, the swagingacting to secure the pulley in place on said shank.

3. In a Venetian blind tilter of the type in which a worm-and-gear areassembled with a supporting structure, the worm'being on a shaft havingan end which projects forwardly from the supporting structure, and saidforwardly projecting end of the shaft being provided with an operatingpulley; the. improvement which comprises: the shaft having a preformedhead on its forwardly projecting end and a square shank behind andadjacent to said head, the shank being enlarged with respect to the sizeof the shaft, the pulley being formed of a pair of duplicate sheet metalmembers apertured to correspond with said shank and located on saidshank, the pulley members having cord-gripping projections in staggeredrelation as assembled on the shank, and the shank being swaged behindsaid pulley whereby the pulley conceals the swaging when the tilter isin use, the swaging acting to clamp the two pulley members together andhold them in place on said shank.

4. For a Venetian blind worm-and-gear tilter, a pulley and shaftassembly comprising: a shaft having a preformed head at one end and apreformed non-circular shank portion adjacent to said head, said shankportion being enlarged with respect to the size of the shaft, andstamped sheet-metal pulley members apertured to correspond with saidenlarged non-circular shank portion and telescopically related thereto,the metal of said shank being swaged to permanently attach the pulleymembers to the shaft.

5. For a Venetian blind worm-and-gear tilter, a

pulley and shaft assembly comprising: a shaft having a head atone endand a non-circular shank portion adjacent to said head, and stampedsheet-metal pulley members apertured to correspond with saidnon-circular shank portion and telescopically related thereto, the metalof said shank being swaged to permanently attach the pulley members tothe shaft.

HANS K. LORENTZEN.

